Peter was first given the keys, but then he was allowed to fall into the sin of denying Christ; and so his pride was humbled by his fall. Do not be surprised, then, if after receiving the keys of spiritual knowledge you fall into various evil thoughts. Glorify our Lord, for He alone is wise: through setbacks of this kind He restrains the presumption that we tend to feel because of our advance in the knowledge of God. Trials and temptations are the reins whereby God in His providence restrains our human arrogance.
A great effort and much toil are needed in prayer before we can reach a state in which our mind is no longer troubled, and so attain the inward heaven of the heart where Christ dwells. As St. Paul says, 'Do you not realize that Christ dwells within you, unless you are worthless?' (cf. 2 Cor. 13:5).
Do you wish God to hear your prayer immediately, brother? When you lift your hands up to heaven, pray first of all, with your heart, for your enemies and God will grant you speedily whatever else you request.
A certain brother asked the Abbot Poemen, saying, 'What am I to do, Father, for I am troubled in sadness?' The old man said to him, 'Look to no man for aught, condemn no man, disparage no man: and God shall give thee rest.'
One of the fathers used to say that some old men were sitting one day and talking of what was useful to the soul. One of them had the gift of vision, and he saw angels who were waving branches in honor of the old men, but when one of them began to speak of irrelevant things the angels withdrew, and some pigs walked amongst the old men bringing a bad smell and messing up everything. As soon as they began once again to speak of what was useful to the soul, the angels returned to do them honor.
This prayer should never be absent from you: 'Lord Jesus Christ, Son and Logos of the living God, through the Theotokos and all the Saints, have mercy upon me, Thy sinful and unworthy servant.' (This is the actual Jesus Prayer: 'O LORD JESUS CHRIST, SON OF GOD, HAVE MERCY UPON ME, A SINNER.') Always say this prayer both with your mouth and with your mind, day and night, wherever you may be, whether eating, walking, working, or sitting. Always meditate on it, as it benefits you a great deal, frees you here from every evil, delivers you there from eternal Hell, and renders you worthy of going to Paradise, our heavenly country.
Prayer is the mind's dialogue with God, in which words of petition are uttered with the intellect riveted wholly on God. For when the mind unceasingly repeats the name of the Lord and the intellect gives its full attention to the invocation of the divine name, the light of the knowledge of God overshadows the entire soul like a luminous cloud.
Do all in your power not to fall, for the strong athlete should not fall. But if you do fall, get up again at once and continue the contest. Even if you fall a thousand times because of the withdrawal of God's grace, rise up again each time, and keep on doing this until the day of your death. For it is written, 'If a righteous man falls down seven times' - that is, repeatedly throughout his life - 'seven times shall he rise again' [Prov. 24:16].
A single word made the thief pure and holy, despite all his previous crimes, and brought him into paradise (cf. Luke 23:42-43). A single ill-advised word prevented Moses from entering the promised land (cf. Num. 20:12). We should not suppose, then, that garrulity is only a minor disease. Lovers of slander and gossip shut themselves out of the kingdom of heaven.
He who chooses maltreatment and dishonor for the sake of truth is walking on the apostolic path; he has taken up the cross and is bound in chains (cf. Mt 16:24). But when he tries to concentrate his attention on the heart without accepting these two, his intellect wanders from the path and he falls into the temptations and snares of the devil.
When Abba Agathon went down to the city to sell some of his baskets and to procure a little bread, he found near the market place an old, poor cripple. 'For the love of God, Abba,' the cripple began to plead on seeing the Saint, 'don't you, too, leave this poor wretch unaided. Bring me near to you.' Abba Agathon picked the man up and sat him next to him in the place where he had set up his baskets to sell them. 'How much money did you make, Abba?' the cripple would ask each time that the Elder sold a basket. 'Such and such,' the Elder would tell him. 'That's good enough,' the cripple finally said. 'Won't you buy me a little pie, Abba? That would be good of you, since I have not eaten since last evening.' 'With pleasure,' the Saint told him, immediately fulfilling the cripple's request. Shortly thereafter, the cripple requested some fruit. And then some sweet. Thus, for each basket that was sold, the Saint spent the proceeds, until, thanks to his patronage, all of the baskets and money were gone, without his having kept even two pennies for himself. More importantly, he did this all with great eagerness, even though he knew that he would thus go perhaps two weeks without any bread for himself. Since he had sold his last basket, the Saint got ready to leave the marketplace. 'So you're going?' the cripple asked him. 'Yes, I have completed all of my work.' 'Uh, do me the favor of taking me as far as the crossroads, and you can leave for the desert from there,' the strange old man again pleadingly said. The good Agathon took the cripple on his back and carried him to the place where he wanted to go, though with great difficulty, since he was exhausted from his day's work. As soon as he reached the crossroads and started to put down his living burden, he heard a sweet voice say to him: 'May you be blessed, Agathon, by God, both on earth and in Heaven.' The Saint raised up his eyes to see who it was who had spoken with him. The would-be old man had completely disappeared, since he was an Angel sent by God to test the Saint's love.
It was said of Abba John the Dwarf that he withdrew and lived in the desert at Scetis with an old man of Thebes. His abba, taking a piece of dry wood, planted it and said to him, 'Water it every day with a bottle of water, until it bears fruit.' Now the water was so far away that he had to leave in the evening and return the following morning. At the end of three years the wood came to life and bore fruit. The old man took some of the fruit and carried it to the church saying to the brethren, 'Take and eat the fruit of obedience.'
An elder prescribes the following rule of conduct for the monastic table: 'When you sit to eat, brother, do not be overcome by the demon of gluttony, which compels you to eat in a disorderly way and in haste and to desire to taste many kinds of food together. Learn to eat modestly and in an orderly way and maintain a measure of restraint.'
The humility which in due time and by God's grace, after many struggles and tears, is given by heaven to those who seek it is something incompararably stronger and higher than the sense of abasement felt by those who have lapsed from holiness. This higher humility is granted only to those who have attained true perfection and are no longer under the sway of sin.